- may be defined as the ability of the film screen combination to record each point in the object as point on the film. - It is used to describe the visibility of diagnostically important detail in radiograph.

The image quality is influenced by many 5 parameters; CDNSR

refers to the difference between adjacent areas in the radiograph. It is mainly made up of SUBJECT CONTRAST, FILM CONTRAST, and FOG and SCATTER.

the difference in x-ray intensities transmitted through different part of the patient.

Subject contrast is affected by? IAD

The fog & scatter will produce unwanted film density which lowers

refers to the density changes caused by the type of film used, how it was exposed, and how it was processed.

Other name of film contrast

The final set of criteria concerns the film and the usage of

A ________ can provide images with greater clarity than a coarse-grain film.

The _________ of the radiation influences the perceived graininess.

As the wavelength shortens and penetration rises, the film's perceived graininess increases or decreases?

In addition, higher film development will make the radiograph appear?

Radiographs with notable density changes (black to white) show high radiographic contrast.

Radiographic pictures with poor radiographic contrast show a minimal density difference between neighboring areas (black to grey).

- The amount of blackness in the radiography picture represents its density. - It is known as "transmitted density" - measures the amount of light that passes through the film

In digital photography, it refers to the movement of the histogram to lower grey levels.

When the ___ increases, the number and energy of x-ray photons generated at the anode increase

higher number of photons with higher energies reaching the receptor leads to an overall increase in the density of the radiographic image at a larger scale when increasing __ or exposure time.

It alters fil density of the image and therefore affects contrast.

Higher ___ increases the energy of X-rays, leading to greater penetration and increased density.

alters the intensity of the beam reaching the image receptor according to the inverse square law.

In traditional radiography, ___ is exposed to radiation passing through the patient and the screen (a phosphorescent material that emits light when exposed to radiation). The ____ _____exposes the film, which is then developed to produce an image.

refers to the ability of the system to distinguish between small details and structures within the image.

ability to image two separate objects and visually distinguish one from the other.

ability to image small structures that have high subject contrast such as bone-soft tissue interface.

ability to distinguish structures with similar subject contrast such as liver-spleen, fat-muscle.

- can cause the image quality to deteriorate. - is an artifact that impairs image sharpness and clarity,

primarily caused by quantum noise or photon scatter during the exposure process, resulting in an uneven distribution of light or radiation on the film.

4 KEY FACTORS CONTRIBUTING TO MOTTLE ILSF

Films with lower sensitivity (low-speed films) require more or less radiation to produce an image?

X-rays are produced at the ____ ____

- area on the anode of the x-ray tube that is hit with electrons from the filament. - All x-ray photons in a beam originate from this

- refers to the distribution in size and space of the silver halide grains in the film emulsion - Similar to structure mottle that refers to the size and shape of the phosphors in the IS.

Similar to photographic film, 400 ASA film is ___ graininess than 100 ASA film. More or less

A primary cause in digital and screen-film radiography, it occurs when too few X-ray photons reach the image receptor, leading to a SPECKLED APPEARANCE. This is common with LOW EXPOSURE LEVELS.

3 Cause of Graininess QFD

Under film grain, In traditional film radiography, the size and distribution of silver halide grains in the film affect the image smoothness. Larger grains contribute to a what appearance?

Under digital noise, In digital radiography, ELECTRONIC INTERFERENCE, LOW SIGNAL LEVELS, or IMAGE PROCESSING can introduce what?

4 FACTORS AFFECTING GRAININESS MKRI

Increasing mAs can reduce _____ _____ by providing more photons to the receptor.

Higher kVp increases penetration but excessive levels may reduce ______, indirectly affecting perceived graininess.

Under Image Processing, Poor algorithm settings in digital systems can Introduce

Under Receptor Sensitivity, ______ _____ with high sensitivity (high DQE) can capture more details with less nolse. Scatter Radiation - Excessive scatter reduces ______ ____ and can contribute to a mottled appearance.

4 WAYS FOR REDUCING GRAININESS IUMU

If the focal spot area is smaller, the image will be spread out less and will appear ____ on the radiograph. An image formed with a small focal spot will display better ________ ______ because the photons originate from a smaller area. As the focal spot size increases, the area of unsharpness _______ (increase or decrease)

produces better recorded detail and spatial resolution

The focal spot size does not change the _____ of photons in the beam or the _____ of those photons. That means that it does not affect IR exposure or _____.

The focal spot size does not change the orientation of the tube, patient and receptor, so it does not affect size or shape distortion. Because the focal spot size does not affect quality or quantity of the beam, this also means it does not affect ____ ____

• The ONLY thing focal spot size affects is

- primary controlling factor of spatial resolution - affects is recorded detail.

does not affect IR exposure because it does not change the number of photons produced or their transmission through the body part.

Focal spot size does not affect _____ ______ because it does not change the penetrability of the beam or the production of scatter